Film pressure shoe and aperture plate assembly for motion-picture projecting apparatus



Nov. 11, 1952 w D'ARCY 2,617,327

FILM PRESSURE SHOE AND APERTURE PLATE ASSEMBLY FOR MOTION-PICTURE PROJECTING APPARATUS Filed Sept. 9, 1950 INVEN,TOR. /7 (fa/7 Y 5 19 3 lftzfor/zey.

Patented Nov. 11, 1952 FILM PRESSURE SHOE AND APER'IURE PLATE ASSEMBLY FOR MOTION-PIC TURE PROJECTING APPARATUS Ellis Wellington D'Arcy, Chicago, Ill., assignor to De Vry Corporation, Chicago, 111., a corporation of Illinois Application September 9, 1950, Serial No. 184,029

1 Claim. 1

This invention relates to new and useful improvements in a film pressure shoe and aperture plate assembly for motion picture projecting apparatuses.

As such, the invention has as its object the provision of an assembly of this character which will be highly efficient in use and economical in manufacture.

A principal object of the invention is to pro-.

vide a simple arrangement for effectively and properly aligning the pressure plate of the shoe in parallel confronting relation with respect to the aperture plate whereby to impose on a film strip an effective uniform pressure for proper film moving operation.

Another object of this invention is to provide in the hereinbefore referred to assembly a pressure plate which is self-aligning with respect to the film channel of the aperture plate.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawings showing the preferred form of construction, and in which:

Fig. lis a perspective view of the aperture plate and pressure shoe embodying my invention showing the same in exploded relation with respect to each other;

Fig. 2 is a fragmentary side elevational view of a lamp housing and projecting lens housing showing my improved film pressure show and aperture plate assembly mounted in an operative position with respect to the lamp housing and projecting lens housing;

Fig. 3 is a front elevational view of the pressure shoe and aperture plate in assembled relation with respect to each other;

Fig. 4 is a fragmentary sectional detail view taken substantially on line 4--4 of Fig. l; and

Fig. 5 is a fragmentary sectional detail view taken substantially on line 55 of Fig. 4.

Referring particularly to the drawings the film aperture plate i indicated at l0 and is formed from an elongated relatively fiat piece of material provided at its upper and lower end portions with bayonet slots l which are adapted to receive the shanks of mounting studs |2 carried by the lamp housing and by means of which the plate I0 is mounted in position upon the housing. These bayonet slots permit ready removal of the plate ID from mounted position. To facilitate this movement I provide a finger piece I 3.

The longitudinal medial portion of the plate l0 provides a film channel having extending along its opposite longitudinal edges tracks l4 over which the long edge portions of a film strip (not shown) pass when intermittently fed through the channel in a manner well known in the art. As these tracks M are raised from the bottom wall of the channel the film strip will be relieved of frictional contact with such bottom wall, thereby to allow smooth movement of the film strip through the channel.

The plate l0 provides a light aperture l5 for projection of the light from the light source within the lamp housing Hi to which the studs |2 are attached. Along opposite side edge portions of the plate |0 there are mounted elongated guide plates H and Il" which together form a pressure plate channel corresponding to the width of the film channel I8 provided by the plate 10. The plate I! is mounted in positionv upon the plate |0 by attaching screws l9. This; plate like the plate ll provides abutments 20; which are turned inwardly, with their inner end. portions 2| projecting into the slots 2|" formed in the plate l0. These abutments 20 are adapted to be engaged by a plate 22 of a pressure shoe 22' hereinafter more fully described, and which shoe includes a mounting plate 3|.

The plate I1 is attached to the plate l0 by slot and screw connections 23 and is normally held in position with the inturned ends of the abutments 2| thereof engaging an adjacent edge of the slots 2| by means of a spring 24 having a. coil embracing a pin. 25 working in a slot 25' and end portions engaging in notches 26 formed in the plate H1. The function of the spring 24 is to resist outward lateral movement of the plate At one side edge of the film channel Hi there are provided lateral spaced studs 21. These studs 21 are adapted to engage the plate 22 of the pressure shoe 22 to guide the plate into proper position l8 upon the tracks M.

This plate 22, like the plate I0, provides along its longitudinal edges tracks 28 which are adapted to be superimposed upon the adjacent long edges of the film strip over the track It.

The plate 22 at its opposite end portions carries lateral studs 29 which project through enlarged openings 30 formed in the mounting plate 3| of the pressure shoe. The studs carry heads 32 by means of which withdrawal of the stud 29 from the openings 30 is prevented. The pressure plate 22 is yieldably spaced from the mounting plate 3| by means of expansion springs 33 disposed between these plates and embracing the studs 29.

Suitable clips 34 are provided at opposite ends of the mounting plate 3|. By means of these clips 34 the pressure shoe is removably attached to lateral extensions 35 of a projecting lens housing supporting bracket. 36, the projecting lens housing being indicated at 37. To facilitate removal of the pressure shoe from mounted position upon the extensions 35 I provide a suitable finger piece 38.

The mounting plate 3| has an enlarged opening 39 exposing the picture aperture 40 formed in the plate 22, which aperture 40 is adapted to register with the aperture l5 o'fth'eplate ID;

A notch portion 4| is formed in the mounting plate 3| and communicates with the opening 39 thereof. This permits entrance" intothe notch 4| of the uppermost stud of the studs- 21 The" openings 30 being of a larger diameter than the diameter of the studs 29, permit alimited-lateral movement between the plate 22 and the mounting plate 3|.

In mounting the pressure shoe 22' upon the aperture plate l0 theedge 42 ofthe pressure plate 22 will'engage the studs Z'I and as these studs are slightly tapered longitudinally the studs will guide the pressure plate into a proper position with thetracksthereof insuperimposed relation with respect to" the con-fronting tracks of the p e By this arrangementthe pressure platen, during the mountingof the pressure shoe in place is self-aligning. Should forany' reason the pressure plate 22 be out ofproper position upon the mounting plate 3| the engagement of the pressure' plate 22' with theg-uide studs 2''! will effect self-alignment of the pressure plate upon the aperture-plate with the track thereof in proper tion' set forth, but' desire toavail myself of such- 0 variations and modifications as" come within the scopeof the appended claim: 4

Having thus described my invention}. What I claim as new and desire to protect by Letters Patent is:

In the combination, an aperture plate having longitudinally extending parallelly related film tracks, a removable pressure shoe comprising a pressure plate, the latter having longitudinally extending parallelly related filintracks adapted for confronting position with respect to the tracks of the aperture plate, plate members on opposite sides of the tracks of the aperture plate providin'g'therebetween a' channel for the pressure plate, for fixedly connecting one of said plate members to said aperture plate, means slidably coimnectirig the'otl'ier of said plate members to said aperture plate, said other plate member adapted to be moved laterally from said channel-forming position by the pressure of one longitudinal edge of said pressure plate when the same is moved into confronting relation with respect to said aperture plate, and spring means carried by saidaperture plate and engaging said other plate member for sliding said other, plate member into channel-forming position with respect to said one plate member, said membersat opposite end portions? on confronting longitudinal' edges having abutment members engageable with" the long edges of the pressure plate; and tapered pin members carried by the aperture plate at one side of said channel and extending 1 outwardly beyond the abutment-members of said one plate memberland adapted for engagement with a long edge of the pressure plate for'fdefiecting'v said pressure plate adjacent said abutment of said one plate memberand into said channel I with the tracks thereof in confronting relation with respect to the tracksflof said, aperture; plate.

ELLIS WELLINGTON DARCY;

' REFERENCES ones The following references" are of record in the file of this patent:

UNITED STATES PATENTS 

